Class D Technology

Is there no need to advance in this direction in raising the switching frequency then?? Too many myself included think it is.

Quote from manufacturer of these new transitors, who btw invented the Mosfet power transistor.

" Higher PWM switching frequencies allow for a higher audio bandwidth, and hence higher-frequency output filters. As a side benefit, this higher-frequency output filter allows for smaller output filter components (especially, the Inductors) without compromising the sonic performance.

In addition to offering higher audio bandwidths (which is increasingly important for the new high-definition audio requirements), the increased PWM switching rates also allow for more moderate output filter slopes, which offer more linear performance without introducing higher levels of residual switching noise."

Cheers George

I've been living with ICEPower based amps for six months, I don't hear any of the issues being discussed, and my speakers have extension beyond 30kHz. 

 
Some folks hear the issues and others don't. Some folks are really sensitive to phase/point source issues or maybe they focus on the image across the soundstage. If someone told me that the image was off, I would just shrug and keep enjoying my gear/music because it's not something that I notice.    

Speakers shift phase much more (in opposite direction) at higher frequencies.  Imaging should be OK as long as phase in both channels match (no reason not to).  As for the switching noise - I cannot hear 500kHz, but I'm pretty sure some people here will claim they can.

I cannot hear 500kHz

Nobody can hear 500khz, it the filter that has to deal with it and what's left over and the byproducts of it that is the problem.

Read the link and carefully try to absorb it.
http://epc-co.com/epc/GaNTalk/Post/13752

Cheers George

Erik,

     I agree with you that, if I can't detect any issues in the audible range on my current class D amps due to their switching frequency being not high enough, than there is no need for concern and I should just enjoy them and my music.  Actually, this is what I've been doing since I installed the amps, I just tried to intently listen for any issues for a short period when I first heard of this theoretical issue.  

      Once an affordable class d amp with a switching frequency in the 3-5 mega hz range is on the market and there are any objective or even subjective reports that it sounds significantly better than current amps, I'll audition one.   I believe this is a more effective approach than not using class D until the theoretical  performance benefits of a 3-5 mega hz switching frequency becomes a reality, since the numerous benefits of class D amplification will not be utilized and enjoyed between now and then.      
      I would think just 2 of class D's benefits, sound quality and electricity cost savings, would be sufficiently convincing for many to switch right now.  If it's only going to get better, upgrade to class D now and then upgrade again whenever you determine future improvements are worth it.  The cost of world-class amplification has never been less expensive,as long as you're willing to be open minded, a bit more adventurous and let your ears guide you.


Enjoy,
 Tim